The purpose of this project is to contribute to the understanding of hormone action on metabolic processes in breast tissue under normal conditions and to understand the failure of or aberrant response to hormones under abnormal conditions. Among the topics studied are the response of mammary tissue in culture to hormones in terms of nucleic acid, protein, glycoprotein and glycosaminoglycansynthesis. The kinds of proteins made by mammary tissue from normal non-pregnant, mid-pregnant, lactating animals and by neoplastic mammary tissue are being analyzed. Response to prolactin and steroid hormones is assessed by chemical and histochemical methods. BIBLIOGRAPHIC REFERENCES: Green, M.R. and Pastewka, J.V.: Molecular weights of three mouse milk caseins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and kappa-like characteristics of a fourth casein. J. Dairy Sci. 59: 1738-1745, 1976.